The present invention relates to a vision guided fastener apparatus and method. More particularly, the present invention relates to a stapler apparatus for assembly of a box spring, or the like, automatically using a vision guided control.
Conventional box springs which are used to support mattresses include a wood frame which supports a plurality of spring modules spaced apart on the wood frame. The modules are coupled to a wire grid which forms the top surface of the box spring. Bottom ends of the modules are typically stapled directly to the wood frame of the box spring.
During conventional assembly of the box spring, a worker must manually staple each of the plurality of modules to the wood frame using an industrial stapler. Therefore, the manufacturing process is limited to the capability of the individual hired to staple the box spring to the modules.
The apparatus of the present invention is designed to automate the box spring stapling process. The apparatus of the present invention includes a vision guided stapling apparatus which automatically locates the modules on the wood frame and then guides the stapler into proper position to secure the modules to the wood frame automatically. The apparatus of the present invention is designed to accommodate different size box springs, such as twin, full, queen, and king sizes. In addition, the apparatus of the present invention may be programmed to secure any type of module to the wood frame of the box spring.
In one illustrated embodiment of the present invention, the apparatus includes a base having two separate sides for supporting two box springs. Therefore, the apparatus can be used to staple modules to a first wood frame on the first side while another box spring is being loaded on the second side of the base. Once the first box spring is completed, the apparatus moves over the second side to staple modules to the second wood frame while another box spring is loaded on to the first side of the apparatus.
According to one aspect of the present invention, an apparatus is provided for securing a plurality of modules to a frame to form a box spring. The apparatus includes a base for supporting the frame and the modules, a support, and a drive mechanism coupled to the support and the base. The drive mechanism is configured to provide relative movement between the support and the base. The apparatus also includes a camera coupled to the support. The camera provides an image signal indicative of an actual position of the modules relative to the frame upon relative movement of the support and the base. The apparatus further includes a tool coupled to the support for securing each of the modules to the frame using the image signal from the camera.
In the illustrated embodiment, the apparatus still further includes a controller for guiding movement of the drive mechanism relative to the base and for controlling movement of the tool to secure each of the modules to the frame as the support moves relative to the frame and the modules located on the base. The controller includes a memory for storing an optimum position for each of the modules on the frame relative to the base. The controller also includes means for guiding the tool to the stored optimum position for securing each module to the frame.
The controller receives the image signal from the camera. The illustrated controller includes means for adjusting the position of the tool from the optimum position to an actual position of the module based upon the image signal to engage the module with the tool. The controller compares the actual position of each module to the optimum position of each module stored in the memory to generate a correction signal to adjust the position of the tool and the module before the module is secured to the frame.
The controller including means for storing an image of the module in the memory, and means for storing at least one designated tool target on the module. The controller compares the image from the camera to the stored module image to control the drive mechanism to move the support and the tool. The controller includes means for calculating position error of the module relative to the frame by comparing the actual image signal from the camera to the stored module image for an optimum module position. The controller also includes means for generating a control signal to move the module to the optimum module position prior to securing the module to the frame. A modem is coupled to the controller for accessing the controller from a remote location.
Also in the illustrated embodiment, the camera is pivotably mounted to the support. The camera pivots about 10.degree. from an initial position aligned generally perpendicular to the base. The tool is also pivotably coupled to the support. Illustratively, the tool is mounted in a gimble coupled to the support. The gimble is pivotable about a first axis and about a second axis normal to the first axis. The tool is also rotatably coupled to the support. The tool is movable from a retracted position to an extended position to engage a module and secure the module to the frame.
The illustrated apparatus includes first and second cameras coupled to the support on opposite sides of the tool. The first camera provides the image signal when the support is moving in a first direction, and the second camera provides the image signal when the support is moving in a second direction. The second camera may provide inspection for the tool when the support is moving in the first direction, and the first camera may provide inspection for the tool when the support is moving in the second direction, if desired.
The illustrated embodiment also includes a bottom gantry movable below the base. The bottom gantry includes an alignment tool configured to position the modules on the frame. The bottom gantry moves the alignment tool relative to the base using a cable drive mechanism.
In one illustrated embodiment, the base includes a first base section for supporting a first frame and a plurality of first modules, and a second base section for supporting a second frame and a plurality of second modules. The drive mechanism is configured to move the support over both the first and second base sections.
According to another aspect of the present invention, a method is provided for securing a plurality of modules to a frame to form a box spring. The method includes the steps of providing a base for supporting the frame and the modules, providing a tool for securing the modules to the frame, storing an image of an optimum position for each of the modules on the frame relative to the base, and providing relative movement between the tool and the base to move the tool to the optimum position for each module. The method further includes the steps of generating an image signal using a camera to indicate an actual position of each module relative to the frame, comparing the optimum position of the module to the actual position of the module, adjusting the position of the tool based on the comparing step, and securing the module to the frame.
The illustrated method further includes the steps of storing a plurality of different optimum positions in the memory corresponding to a plurality of different frame and module configurations, and selecting a particular frame and module configuration based upon the actual frame and module configurations that are located on the base.
The method further includes the step of determining whether the module should be moved by the tool relative to the frame based on the comparing step before the tool secures the module to the frame in the securing step. The illustrated method also includes the step of aligning the modules on the frame substantially in the optimum position prior to the securing step.
According to yet another aspect of the present invention, an apparatus is provided for securing a module to a frame. The apparatus includes a base for supporting the frame and the modules, a support including a track extending across the frame, and a first drive mechanism coupled to the support and the base. The first drive mechanism is configured to move the support along a first axis over the base. The apparatus also includes a fastener assembly including a plate movably coupled to the track of the support for movement along a second axis which is generally perpendicular to the first axis, a gimble pivotably coupled to the plate about both the first axis and the second axis, and a tool coupled to the gimble for movement about a longitudinal axis for securing the module to the frame. The apparatus further includes a second drive mechanism coupled between the support and the plate for moving the plate along the second axis relative to the support, a third drive mechanism coupled between the plate and the gimble for pivoting the gimble about the first axis, a fourth drive mechanism coupled between to the plate and the gimble for pivoting the gimble about the second axis, and a fifth drive mechanism coupled to the tool for moving the tool up and down along its longitudinal axis. The apparatus still further includes a controller coupled to and configured to actuate the first, second, third, fourth, and fifth drive mechanisms for guiding movement of the support, the plate, the gimble, and the tool to secure the module to the frame.
The illustrated apparatus further includes a camera coupled to the support. The camera provides an image signal indicative of an actual position of the module relative to the frame upon movement of the support relative to the base. The controller includes means for storing an optimum position of each module relative to the frame, means for moving the tool to the optimum position, means for comparing the optimum position to the actual position of the module based on the image signal from the camera, and means for adjusting the position of the tool to engage the module.
According to still another aspect of the present invention, an apparatus for controlling a stepper motor includes a motor driver coupled to the stepper motor. The motor driver provides an output signal to the stepper motor to index the stepper motor. The motor driver also sets a micro-step resolution for the stepper motor. The apparatus also includes a controller coupled to the motor driver. The controller transmits control data to the motor driver for instructing the motor driver whether to index the stepper motor and whether to change the micro-step resolution setting. The motor driver is configured to decode the control data received from the controller, to index the stepper motor, and to change the micro-step resolution setting during continued operation of the stepper motor.
In the illustrated embodiment, the control data includes first data for instructing the motor driver whether to change the micro-step resolution setting of the stepper motor, and second data to representing the desired new micro-step resolution setting. Also illustratively, the control data is a serial byte of data. The first data includes a first data bit, and the second data includes at least three data bits to provide a plurality of different desired the micro-step resolution settings for the stepper motor.
The controller transmits data to the motor driver at a preset period to control a micro-step rate of the stepper motor. The period is adjustable during operation of the stepper motor to change the micro-step rate of the stepper motor.
According to an additional embodiment of the present invention, an apparatus for controlling a stepper motor includes a motor driver coupled to the stepper motor. The motor driver provides an output signal to the stepper motor to index the stepper motor. The motor driver also sets a power level at which the stepper motor is operated. The apparatus also includes a controller coupled to the motor driver. The controller transmits control data to the motor driver for instructing the motor driver whether to index the stepper motor and whether to change the power level setting. The motor driver being configured to decode the control data received from the controller, to index the stepper motor, and to change the power level setting during continued operation of the stepper motor.
In the illustrated embodiment, the control data includes first data for instructing the motor driver whether to change the power level setting of the stepper motor, and second data to representing the desired new power level setting. The first data illustratively includes a first data bit, and the second data includes at least three data bits to provide a plurality of different power level settings for the stepper motor.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.